Given tanB = fifteen-ninths find angle B in degrees.

B = inverse tan (15/9) = arc tan (15/9)

tan^-1(15/9)= atan(15/9)

The Web2 calculator uses the atan version.  To bring itup press 2nd first.

$$\underset{\,\,\,\,^{\textcolor[rgb]{0.66,0.66,0.66}{360^\circ}}}{{tan}}^{\!\!\mathtt{-1}}{\left({\frac{{\mathtt{15}}}{{\mathtt{9}}}}\right)} = {\mathtt{59.036\: \!243\: \!467\: \!926^{\circ}}}$$

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